Clemens lohmann



NITED STATES CLEMENS. LOHMANN, OF

UATENT, anion.

COLOGNE-ON-THE-RHINE, PRUSSIA, GERMANY.

SPECIFICATION forming part of Letters Patent No. 354,714, dated December21, 1886.

Application filed June 28, 1886. Serial No. 206,497. (Specimens) To allwhom it may concern.-

Be it known that I, CLEMENS LOHMANN, a subject of the'King of Prussia,and residing at Oologne-on-the-Rhine, Kingdom of Prussia, Germany, haveinvented new and useful Improvements in Dyeing Blue, especially adaptedfor wool, whereof the following is a specification.

My invention consists in a new process for dyeing wool and other animalfibrous materials blue, which isperformable more easily and at a lowercost than the present process of dyeing with indigo, and whereby aperfectly fast or unchangeable coloring is obtained.

The dyeing substances used in the process are azodiphenyl blue, extractof logwood, (Oampeachy wood,) blue vitriol, (sulphate of peroxide ofcopper,) and green vitriol, (sulphate of protoxide of iron.) These areadvantageously mixed in the following proportion: thirty-four pounds ofazodiphenyl blue; thirty pounds of extract of logwood, (weighed in drystate;)sixteen pounds of blue vitriol; twenty pounds of green vitriol;but from these "'proportional numbers deviations may take place.

In preparing the dyeing-bath an alkalic bisulphate, preferablybisulphate of soda, and oxalic acid are added to the said mixture.

For a dark-blue color it is advisable to employ upon one hundred poundsof wool ten pounds of the mixture, ten pounds of bisulphate of soda, andsix pounds of oxalic acid. Lighter tints require of all substancespropor- 3 5 tionately less. The substances are mixed and treated withhot water for dissolving them, and their solution may be promoted byboiling. Subsequently so much cold water is added to the liquor thusobtained as is required for a bath 0 adapted to contain the quantity ofwool to be dyed. The wool, previously moistened, is then brought intothe bath and efiiiciently permitted the dyeing operations to be perboiled for about an hour and a half. It tints darker than those to beobtained from this bath aredesired, they may be produced by a furtheraddition of blue vitriol, (about five pounds to one hundred pounds ofwool,) and by continuing to boil until'the desired shade is attained. I

In one bath repeated dyeing operations may be carried out, provided thatthe substances absorbed by the Wool in one operation be replaced for thenext one.

The described process is adapted for dyeing loose wool and other animalfibrous materials, as well as the yarns and cloths prepared therefrom.The color is not affected bywashing, byligh t, and by air, and it iscompletely resistant against acids. The process rcquires but a singlebath without previous boiling 0r mordanting of the material to be dyed,and its cost is but about the fourth part of that of dyeing with indigo.I

I am aware that the various agents used in my process have before beenused separately and in other combinations for dyeing pur-' poses; butnone of such combinations has resulted in a blue that is lasting againstall influences, and none, so far as I am aware, has

formed in one single bath.

I claim as my invention The process of dyeing wool and other animalfibrous materials blue by boiling them in a watery solution ofazodiphenyl blue, extract of logwood, blue vitriol, green vitriol, analkalicbisulphate, and oxalic acid, substantially as hereinbeforespecified.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing 8o witnesses.

. CLEMENS LOHMANN.

Witnesses:

HENRY SPRINGMANN, B. R01.

